Toronto, San Fran, Columbus, NYC: Open-mics or house shows?

At the end of this month I'm going to be taking a much-needed two week break from work and jetting around North America to visit friends, check out my future grad school, and shop for records. Into this I think it'd be really fun to incorporate playing a few shows, my first "world tour." So, if anybody knows of any parties going on or receptive open-mic audiences or desperate booking people looking for a novelty opening act on these dates, I'd REALLY love to know:

Columbus, Ohio: Tuesday 3/28, Wednesday 3/29, Thursday 3/30
New York, New York: Saturday 4/01, Sunday 4/02, Monday 4/03
Toronto, Ontario: Tuesday 4/04, Wednesday 4/05, Thursday 4/06
San Francisco, California: Saturday 4/08, Sunday 4/09

To have some idea of what kind of stuff I do, check out my MySpace. I'll be travelling with a boom box, a microphone, and my most portable of keyboards, so this is going to be a somewhat lo-fi Doctor Casino.

Also, while I'm on the subject, the usual "I'm travelling, where are the great record stores" type questions apply... thanks tremendously to any and all respondents.